1. Technical Field
The present invention generally relates to an apparatus and method to perform vehicle engine diagnostic tests. More particularly, the present invention pertains to an arrangement to simulate turbocharger operation without running the vehicle engine.
2. Discussion
Vehicles having engines equipped with turbochargers have presented a challenge to service technicians and other repair personnel attempting to diagnose the cause of a customer complaint. The diagnosis is challenging due to the method in which the turbocharger functions. As is commonly known, a turbocharger is an air pump used to increase the volume of air entering into the combustion chamber of the engine. The increased air volume thereby increases the power output of the engine. The turbocharger is driven by a turbine located in the exhaust gas path. Accordingly, as engine speed increases, exhaust gas volume increases to turn the turbine at an increased rate. Subsequently, intake air pressure, or boost, also increases. Using this mechanism, the turbocharger supplies a charge of air to the engine at a pressure greater than atmospheric pressure. Therefore, to properly diagnose turbocharger operation, air pressures greater than atmospheric must be generated. Unfortunately, the higher pressures have typically been generated by running the engine at a relatively high speed while attempting to diagnose the problem.
Performing engine diagnostics while the engine is operating at a very high speed it is undesirable for a variety of reasons. When an engine is operating near maximum RPM, its power output is also near its maximum. If the energy is inadvertently released, the likelihood of damage to engine components and service personnel working nearby is high. Additionally, the difficulty of diagnosing a leak within the intake air system greatly increases because of the noise generated from the engine operating at a high speed.
Accordingly, it is an object of the present invention to provide a method and apparatus for engine diagnostics by generating the boost pressure created by a turbocharger without requiring the engine to be running.
It is another object of the present invention to provide a portable, cost effective tool for variably pressurizing the charge air cooling system of an engine equipped with a turbocharger.
It is yet another object of the present invention to provide a method and apparatus for quickly and accurately determining the cause of a customer complaint associated with the turbocharger system.
The present invention pertains to an engine diagnostic tool for simulating turbocharger operation within an engine of a motor vehicle while the engine is not running. The turbocharger includes an air inlet having an inner surface and an outer surface. The diagnostic tool includes a plug adapted to sealingly engage the inlet of the turbo. The plug includes an aperture for supplying pressurized air to the inlet. The diagnostic tool also includes a clamp adapted to selectively restrict movement of the plug relative to the inlet. The clamp is adapted to be removably coupled to the inlet.